I just completed the Semroc Mars Lander and upgraded the motor mount to 24mm. The kit is terrific, with high quality parts throughout. Now I'm waiting for a reasonably good day to fly it!

http://www.postimage.org/image.php?v=Pq4tZOr

Um...how much nose weight did you add? The thing is marginally stable on 18mm in low winds, so going 24mm would be a bit risky. Hopefully you checked out the excellent cover story in Sport Rocketry a couple months ago detailing out various mods and simulations on this, including I think a 24mm option.

I'd also go for a quick spike 24mm like an E15 or E30, versus something like an E9. Anything to improve velocity off the rod would be a very good thing...

--Chan Stevens

Not sure how the Semroc version weighs out, but my Tango Papa 24mm version flies well on D12-3's. There is about .5 ounce of lead in the nose. My first flight was a CATO, which I filled a MESS report on (at NSA in Orangeburg this year). Some of you may remember the pics I posted of it actually blowing up; neat stop-action. It has since been repaired and has been flown; had to replace the inner BT completely! It has a scar or two, but I guess it has some character now!
Pic was taken just before the fireball came out the top! I have those pics as well, but they are on the home computer.
Allen

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Yeah, that Tango Papa is a sweet kit, but it is an upSCALE, and RocketDog says he did an upGRADE, which I presume is just sub'ing out the motor mount and centering rings. Folks have done similar mods to the Estes Outlander, which tends to work fine, but it's got a lot different drag profile and probably different stability margin as well.

Thanks, Chan,
I did not realize it was an upscale. I thought it was 'about' the same as the Estes, but you are correct, as usual!
Allen

Yes, I just substituted a new motor mount. I plan to fly it on C11's at first. Altpred shows anything less than a C probably crashing this bird.

Chan, what issue of Sport Rocketry contained that article? I don't have it and would like to get it, or at least the article if possible.

Dog

Me two!

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Bob
NAR 77103

I'm fairly sure it was the May/June 2008 issue, but don't have the issue handy here at work. My memory's usually pretty reliable for about 6 months, though, so you can count on that issue as almost certainly the right one. Anything beyond 6 months, though, seems to get jettisoned from the ol' memory banks .

The 24mm Tango-Papa kit is NOT an upscale Mars lander, it is his 1X kit.
He has a 1X-24mm, a 1.6X-29mm, and a 2X-38mm kit.
The 1X-24mm is considerably heavier than the original or Semroc CC kit.

The May/June Sport rocketry has the ML right on the cover.

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ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

GH,

That's what I thought, too. I was gonna reply with a similar argument. Then I looked up the numbers. It's a 1.07x upscale (LOC3.9" vs BT100, 4"/3.744"=1.0684). Not huge, but not trivial either.

The key point is that the Tango Papa kit is proven stable on a 24mm motor. But anyone flying a true clone of the Estes kit would likely need to make some mod's / add some noseweight in order to use a 24mm motor.

Doug

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